Computations have been widely used to explore new Li ion battery materials because of its remarkable advantages. In this review, we summarize the recent progress on computational investigation on anode materials in Li...Computations have been widely used to explore new Li ion battery materials because of its remarkable advantages. In this review, we summarize the recent progress on computational investigation on anode materials in Li ion batteries. By introducing the computational studies on Li storage capability in carbon nanotubes, graphene, alloys and oxides, we reveal that computations have successfully addressed many fundamental problems and are powerful tools to understand and design new anode materials for Li ion batteries.展开更多
Since Akira Yoshino first proposed the usage of the carbonaceous materials as an anode of lithium ion batteries(LIBs)in 1985,carbonaceous materials such as graphite and graphene have been widely considered as LIB anod...Since Akira Yoshino first proposed the usage of the carbonaceous materials as an anode of lithium ion batteries(LIBs)in 1985,carbonaceous materials such as graphite and graphene have been widely considered as LIB anodes.Here,we explored the application of novel carbonaceous UB anodes incorporating graphene quantum dots(GQDs).We fabricated a freestanding all-carbon electrode based on a porous carbon nanotube(CNT)sponge via a facile in-situ hydrothermal deposition technique,creating coaxial structure of GQD-coated CNTs(GQD@CNTs)through electrostatic interaction and n-n stacking with tunable loading and functionalization.This hybrid structure combined conductive CNTs with highly active GQDs,in which GQDs with predesigned functional groups provided massive storage sites for Li ions and the 3D CNT frameworks avoided the agglomeration of GQDs,together contributing to a high specific capacity(700 mAh·g^-1 at 100 mA·g^-1 after 100 cycles)and rate performance.Even at a high current density of 1,000 mA·g^-1,the reversible specific capacity remained at 483 mAh g-1 after 350 cycles.In particular,the mechanism study demonstrated the important role of oxygen functional groups of GQDs in promoting the performance of the LIB anodes by controlled grafting of GQDs onto various porous-carbon and metal-foam based structures.展开更多
Sn O2理论上的可逆锂贮存容量为790 m Ah/g,这是当前使用的石墨的理论容量372 m Ah/g的两倍以上,然而其循环性能较差。研究发现,Sn O2和碳基体的复合可以有效的改善其循环性能,文章综述了的不同形貌结构的Sn O2/C复合材料的可控合成,以...Sn O2理论上的可逆锂贮存容量为790 m Ah/g,这是当前使用的石墨的理论容量372 m Ah/g的两倍以上,然而其循环性能较差。研究发现,Sn O2和碳基体的复合可以有效的改善其循环性能,文章综述了的不同形貌结构的Sn O2/C复合材料的可控合成,以及分析总结了其形貌对其可逆容量和循环性能的影响。展开更多
通过氧化石墨烯(GO)和壳聚糖(Cs)之间的氢键以及静电作用形成GO水凝胶,从而将纳米硅颗粒和碳纳米管(CNT)原位包封于其中,再经冷冻干燥及随后的热处理制得三维硅/碳纳米管/石墨烯(Si-CNT@G)纳米复合材料。采用X射线衍射(XRD)、扫描电子...通过氧化石墨烯(GO)和壳聚糖(Cs)之间的氢键以及静电作用形成GO水凝胶,从而将纳米硅颗粒和碳纳米管(CNT)原位包封于其中,再经冷冻干燥及随后的热处理制得三维硅/碳纳米管/石墨烯(Si-CNT@G)纳米复合材料。采用X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)、热重分析(TGA)等技术对制得样品的物相、结构和微观形貌等进行了表征。结果表明,所得复合材料在CNT纵横交织的石墨烯网络中,均匀地分布着纳米硅颗粒。当作为锂离子电池的负极材料时,在两种碳介质的协同作用下,有效缓冲硅材料在充放电过程中脱/嵌锂引起的体积变化,缩短了锂离子和电子传输的距离,Si-CNT@G复合材料表现出较好的循环稳定性以及倍率性能。在500 m A·g^-1的充放电电流密度下,经过200圈循环后,其放电比容量仍高达673.7 m Ah·g^-1,容量保持率高达97%;即使将充放电电流密度升至2000 m A·g^-1时,该复合材料仍保持有566.9 m Ah·g^-1的高可逆放电比容量。独特的制备方法和优越的储锂性能,使得Si-CNT@G纳米复合材料成为理想的高性能锂离子电池负极材料的候选.展开更多
在超声环境下,采用强氧化法将多壁碳纳米管(MWCNTs)切割成长径比小于5的超短碳纳米管(SSCNTs),通过简单的湿化学法将其与MnO_x纳米颗粒(MnxNPs)植入还原性氧化石墨烯片层中,热处理后,形成GS-SSCNTs-MnNPs纳米复合材料.通过扫描电子显微...在超声环境下,采用强氧化法将多壁碳纳米管(MWCNTs)切割成长径比小于5的超短碳纳米管(SSCNTs),通过简单的湿化学法将其与MnO_x纳米颗粒(MnxNPs)植入还原性氧化石墨烯片层中,热处理后,形成GS-SSCNTs-MnNPs纳米复合材料.通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X-射线衍射(XRD)等制备材料的形貌结构,采用循环伏安和恒流充放电研究其锂离子电池负极性能.结果表明:GS-SSCNTs-MnNPs纳米复合材料在180 m A·g^(-1)电流密度下具有高达1 100 m A·h·g^(-1)的可逆容量,且表现出优异的功率和循环稳定性能,循环100圈之后,仍具有高达837 m A·h·g^(-1)的可逆容量(1 440 m A·g^(-1)).展开更多
文摘Computations have been widely used to explore new Li ion battery materials because of its remarkable advantages. In this review, we summarize the recent progress on computational investigation on anode materials in Li ion batteries. By introducing the computational studies on Li storage capability in carbon nanotubes, graphene, alloys and oxides, we reveal that computations have successfully addressed many fundamental problems and are powerful tools to understand and design new anode materials for Li ion batteries.
基金A.Y.C.appreciated the financial support from the National Natural Science Foundation o f C hina(No.51672005).S.Y.Y.appreciated the financial support from the National Natural Science Foundation of China(No.51872267).Z.X.W.thanks Qihang Gong for his support and encouragement all the time.
文摘Since Akira Yoshino first proposed the usage of the carbonaceous materials as an anode of lithium ion batteries(LIBs)in 1985,carbonaceous materials such as graphite and graphene have been widely considered as LIB anodes.Here,we explored the application of novel carbonaceous UB anodes incorporating graphene quantum dots(GQDs).We fabricated a freestanding all-carbon electrode based on a porous carbon nanotube(CNT)sponge via a facile in-situ hydrothermal deposition technique,creating coaxial structure of GQD-coated CNTs(GQD@CNTs)through electrostatic interaction and n-n stacking with tunable loading and functionalization.This hybrid structure combined conductive CNTs with highly active GQDs,in which GQDs with predesigned functional groups provided massive storage sites for Li ions and the 3D CNT frameworks avoided the agglomeration of GQDs,together contributing to a high specific capacity(700 mAh·g^-1 at 100 mA·g^-1 after 100 cycles)and rate performance.Even at a high current density of 1,000 mA·g^-1,the reversible specific capacity remained at 483 mAh g-1 after 350 cycles.In particular,the mechanism study demonstrated the important role of oxygen functional groups of GQDs in promoting the performance of the LIB anodes by controlled grafting of GQDs onto various porous-carbon and metal-foam based structures.
文摘Sn O2理论上的可逆锂贮存容量为790 m Ah/g,这是当前使用的石墨的理论容量372 m Ah/g的两倍以上,然而其循环性能较差。研究发现,Sn O2和碳基体的复合可以有效的改善其循环性能,文章综述了的不同形貌结构的Sn O2/C复合材料的可控合成,以及分析总结了其形貌对其可逆容量和循环性能的影响。
文摘通过氧化石墨烯(GO)和壳聚糖(Cs)之间的氢键以及静电作用形成GO水凝胶,从而将纳米硅颗粒和碳纳米管(CNT)原位包封于其中,再经冷冻干燥及随后的热处理制得三维硅/碳纳米管/石墨烯(Si-CNT@G)纳米复合材料。采用X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)、热重分析(TGA)等技术对制得样品的物相、结构和微观形貌等进行了表征。结果表明,所得复合材料在CNT纵横交织的石墨烯网络中,均匀地分布着纳米硅颗粒。当作为锂离子电池的负极材料时,在两种碳介质的协同作用下,有效缓冲硅材料在充放电过程中脱/嵌锂引起的体积变化,缩短了锂离子和电子传输的距离,Si-CNT@G复合材料表现出较好的循环稳定性以及倍率性能。在500 m A·g^-1的充放电电流密度下,经过200圈循环后,其放电比容量仍高达673.7 m Ah·g^-1,容量保持率高达97%;即使将充放电电流密度升至2000 m A·g^-1时,该复合材料仍保持有566.9 m Ah·g^-1的高可逆放电比容量。独特的制备方法和优越的储锂性能,使得Si-CNT@G纳米复合材料成为理想的高性能锂离子电池负极材料的候选.
文摘在超声环境下,采用强氧化法将多壁碳纳米管(MWCNTs)切割成长径比小于5的超短碳纳米管(SSCNTs),通过简单的湿化学法将其与MnO_x纳米颗粒(MnxNPs)植入还原性氧化石墨烯片层中,热处理后,形成GS-SSCNTs-MnNPs纳米复合材料.通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X-射线衍射(XRD)等制备材料的形貌结构,采用循环伏安和恒流充放电研究其锂离子电池负极性能.结果表明:GS-SSCNTs-MnNPs纳米复合材料在180 m A·g^(-1)电流密度下具有高达1 100 m A·h·g^(-1)的可逆容量,且表现出优异的功率和循环稳定性能,循环100圈之后,仍具有高达837 m A·h·g^(-1)的可逆容量(1 440 m A·g^(-1)).
